48÷2(9+3) = ?

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Reply 460

CameraGirl

suuuuuuuuuuurely this is a troll?!?!

brackets first, as always -> 9+3 = 12, times 2 = 24
48 / 24 = 2.

yes.

Reply 461

CameraGirl

Original post by mangoh

lol I can take it :smile:

, it's a forum to discuss... of course listen to what the mod says but if you politely suggest why I am wrong then it should be fine.

BUT... I doubt u can as I am clearly right.

are you trolling? no offence.
i saw your answer, you did (9+3) = 12, + 2 = 14.
but it's 2(9+3) which is (9+3) = 12, times 2 = 24
48 / 24 = 2.

how has this caused so much debate?!

Reply 462

Hanvyj

Original post by CameraGirl

are you trolling? no offence.
i saw your answer, you did (9+3) = 12, + 2 = 14.
but it's 2(9+3) which is (9+3) = 12, times 2 = 24
48 / 24 = 2.

how has this caused so much debate?!

BODMAS that you learn in school states you should divide before multiplying. Hence, according to that, what you did was wrong (divide 48 by 2, times by 12 = 288)

Reply 463

mangoh

Original post by CameraGirl

are you trolling? no offence.
i saw your answer, you did (9+3) = 12, + 2 = 14.
but it's 2(9+3) which is (9+3) = 12, times 2 = 24
48 / 24 = 2.

how has this caused so much debate?!

first of all any need to double post :l, why not delete your post/edit it :l

and second, I know what I am talking about, I'm fairly good at maths.

I did the brackets first, you have to add 12 to 2 :l

Reply 464

CameraGirl

Original post by Hanvyj

http://www.wolframalpha.com/input/?i=48%2F2*x+at+x%3D12

its 288!

No, seriously I don't know.

First thought was 2.

After reading (and realising division was before multiplication in BODMAS) i thought 288.

Now apparently these differ according to wolframalpha:

1/2*x and 1/2x - this makes sense to me, and now I am thinking 2 again... I think BODMAS was just some wierd thing they invented for school that just doesn't apply...

wolfram alpha is indeed godly, but can be dodgy if you don't use brackets right etc.

division may come first in BODMAS, but since the 2 is part of the brackets, you do that first. 2(9+3), the 2 is part of the bracketed bit, hence you would calculate that entire bit seperately to the 48. so yeah. it's 2.

Original post by mangoh

pleeeeeeeeeease tell me you are a massive troll? :P
any qualifications in maths?
lulz you're just so wrong it's funny.

ps. yeaaaaaah i have a bad habit of double posting. you'll get over it.

(edited 13 years ago)

Reply 465

connor ellis

http://www.mathsisfun.com/operation-order-bodmas.html

The answer technically is 288 because when you cannot decipher clearly wether to divide or multiply first you work from left to right. (As shown in the link provided.)

so working from left to right,
48÷2(9+3)
(48/2)(9+3)
24*12= 288

By the way I initially thought 2 but it isn't as simple as it looks.

Reply 466

connor ellis

The fact the 'D' comes first in bodmas doesnt matter. the D and the M are of equal priority. The Bodmas rule can be misleading.

Bidmas/bodmas

Original post by Hanvyj

BODMAS that you learn in school states you should divide before multiplying. Hence, according to that, what you did was wrong (divide 48 by 2, times by 12 = 288)

Original post by connor ellis

see above. if you rearrange it as a fraction it is just so easy, which is the proper way to do it, the division sign is jsut so kids can understand fractions differently.

(edited 13 years ago)

Reply 469

ily_em

Only on TSR would this thread still be going :rolleyes:

Reply 470

Inzamam99

It's 288, simple BODMAS.

Reply 471

Haddock3

Original post by CameraGirl

a) Yes, mangoh is clearly trolling. Forget him.
b) Don't be so sure, without a fraction written vertically you can't be sure that the (9+3) shouldn't be on the top of the fraction, as would usually be the convention. Its basically ambiguous notation as we've all agreed, since there are two conflicting conventions at work. It can be either 2 or 288.

Reply 472

Spungo

Oh jolly good, these questions always spur a wealth of intelligent and interesting arguments.

What is the best way to answer this question?

Spoiler

-Insert sarcasm quotes where applicable.

Reply 473

Hanvyj

Original post by CameraGirl

see above. the 2 is part of the brackets, it's involved with the brackets not the 48.
if you wrote it out as a fraction you'd have:

48
--------
2(9+3)

i am doing maths with my degree. waaaaaay beyong bodmas and i think i'd be majorly stuffed if i couldnt even do that.

see above. if you rearrange it as a fraction it is just so easy, which is the proper way to do it, the division sign is jsut so kids can understand fractions differently.

I happen to agree, I was just pointing out where the debate came from. I did physics at uni and that is how I would have done it. I don't think I ever saw a division sign at Uni.

(edited 13 years ago)

Reply 474

maturestudy

Original post by Jallenbah

Ok let me just make this very clear.

Multiplication and Division have EQUAL precedence
BIDMAS is an oversimplification of operator precedence taught to childeren. In reality, Multiplication and Division are equal, as are Addition and Subtraction.
What this means is that when you encounter a sum with them both, you do it left to right.

QFT!

Reply 475

CameraGirl

guuuuuuuuys. i demonstrate:

had it been written 48/2x9+3 then there would have been no way of telling when to divide/multiply.
if it were (48/2)(9+3) then you would divide the 48 by 2 then multiply and get 288.
48/2(9+3), the 2 is clearly multiplying what's inside the bracket. that is just how maths works.
re-written as a fraction for clarity:

48
----
2(9+3)

= 2

Original post by Hanvyj

I happen to agree, I was just pointing out where the debate came from. I did physics at uni and that is how I would have done it. I don't think I ever saw a division sign at Uni.

aaaah ok haha. yeah i can't say i've seen a division sign since year 9 SATS if i'm honest!

i get how it could be misleading, but the 2 clearly goes with the brackets, else the whole problem would have to be re-written with differently placed brackets, around the 48. the 2 is only referring to that which is inside the brackets. reminds me of the chain rule of calculus haha.

(edited 13 years ago)

Reply 476

py0alb

Original post by CameraGirl

i am doing maths with my degree. waaaaaay beyong bodmas and i think i'd be majorly stuffed if i couldnt even do that.

yeah you would be stuffed lol, good job you got it right eh! :smile:

Reply 477

connor ellis

Original post by CameraGirl

see above. if you rearrange it as a fraction it is just so easy, which is the proper way to do it, the division sign is jsut so kids can understand fractions differently.

But you cannot take it as a fraction. you could if it was 48/(2(9+3)) then the answer would be 2. However as it is written 48/2(9+3) The 9+3 part is not necessarily on the lower half of the fraction. Using Bodmas properly the answer is 288 no doubt.